When it comes to information gathering by the National Security Agency, members of Congress have no special protections.

Friday, Vermont’s independent U.S. Sen. Bernard Sanders sent a letter to Gen. Keith Alexander, director of the NSA, asking if his agency is “spying’ on members of Congress.

“I am writing today to ask you one very simple question,” Sanders wrote. “Has the NSA spied, or is the NSA currently spying, on members of Congress or other American elected officials?”

In the letter, Sanders defined spying as “gathering metadata on calls made from official or personal phones, content from websites visited or emails sent, or collecting any other data from a third party not made available to the general public in the regular course of business.”

“I have not gotten a formal response to my letter, but I expect one very shortly,” Sanders said in an interview Monday.

Over the weekend, the NSA issued a press release addressing Sanders’ question.

“NSA’s authorities to collect signals intelligence data include procedures that protect the privacy of U.S. persons,” the statement said. “Such protections are built into and cut across the entire process. Members of Congress have the same privacy protections as all U.S. persons.”

Leaked information from former NSA contractor Edward Snowden revealed the NSA collects the phone records of millions of Americans.

“I raised this question because I want to make clear to the American people how dangerous this is,” Sanders said Monday. “The NSA has the ability to blackmail and embarrass members of Congress.”

Sanders drew parallels to the Watergate scandal as he addressed the possibility of the NSA leaking information about a political campaign.

“You look at all the things (President Richard) Nixon did,” Sanders said. “If you have an unscrupulous president or a rogue member of the NSA, they would have powers Richard Nixon would only have dreamed of.”

In June, Sanders introduced a bill in the U.S. Senate addressing NSA surveillance. The bill, S. 1168, titled the “Restore Our Privacy Act,” seeks to “limit overbroad surveillance requests” by requiring the NSA to provide evidence to support their surveillance actions.